There is known a centrifugal compressor in which a movable vane movable between a projecting position where it is projected into a diffuser portion and a housing position where it is housed in a housing chamber provided in a diffuser wall is provided in the diffuser portion. For example, there is known a centrifugal compressor in which the inside of the housing chamber is divided into two spaces by a partition member equipped with the movable vane and the partition member is moved by a pressure difference between the two spaces and a spring provided in one space so as to house the movable vane in the other space or to project the movable vane toward the diffuser portion (see Patent Literature 1).